Thomas F Gajewski

University of Illinois at Chicago, Chicago, Illinois, United States

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Publications (201)1370.2 Total impact

  • Thomas F. Gajewski, Leticia Corrales
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    ABSTRACT: Although type I IFNs were initially described based on their anti-viral properties, it was quickly realized that these cytokines had anti-proliferative and anti-cancer activities. These observations ultimately led to the clinical development and utility of IFN-α2b for the treatment of patients with melanoma, renal cell carcinoma, and chronic myelogenous leukemia, among others. However, the mechanism of action of type I IFNs in vivo was never fully elucidated, and the pleiotropic effects of IFNs on multiple cell types had made it challenging to decipher. Advancement of genetically engineered mouse models has provided new tools for interrogating these mechanisms. Recent evidence has indicated that spontaneous innate immune sensing of cancers that leads to adaptive immune responses is dependent on host type I IFN production and signaling. The major innate immune receptor pathway that leads to type I IFN production in response to a growing tumor appears to be the STING pathway of cytosolic DNA sensing. STING agonists drive type I IFN production and are impressively therapeutic in mouse tumor models. Targeting low doses of type I IFNs to the tumor microenvironment also promotes anti-tumor activity via host adaptive immunity that is T cell-dependent. However, high doses of intratumoral type I IFNs largely function via an anti-angiogenic effect. Understanding these mechanistic details should enable improved clinical manipulation of the type I IFN system in cancer.
    Cytokine & Growth Factor Reviews. 01/2015;
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    ABSTRACT: BACKROUND In patients with metastatic melanoma and KIT amplifications and/or mutations, therapy with imatinib mesylate may prolong survival. 18F-labeled 2-fluoro-2-deoxy-D-glucose (18F-FDG) PET/CT may be used to assess metabolic response. We investigated associations of metabolic response, mutational status, progression-free survival and overall survival in this population. METHODS: Baseline and 4-week follow-up 18F-FDG-PET/CT were evaluated in 17 patients with metastatic melanoma and KIT amplifications and/or mutations treated with imatinib in a multicenter phase II clinical trial. The maximum standardized uptake values (SUVmax) were measured in up to 10 lesions on each scan. Metabolic response was classified using modified EORTC criteria. Each patient had a diagnostic CT or MR at baseline, after 6 weeks of therapy and then at intervals of 2 months and anatomic response was classified using RECIST 1.0. Median follow-up was 9.8 months. RESULTS: Partial metabolic response (PMR), stable metabolic disease (SMD) and progressive metabolic disease (PMD) was seen in 5 (29%), 5 (29%), and 7 (41%) patients respectively. Five patients (29%) had a KIT mutation in exon 11, four of whom (80%) had PMR while 1 (20%) had SMD. Twelve patients (71%) did not have a KIT mutation in exon 11, and only 1 (8%) had PMR, 4 (33%) had SMD and 7 (58%) had PMD. There was agreement of metabolic and anatomic classification in 12 of 17 patients (71%). Four of 17 patients (24%) had PR on both metabolic and anatomic imaging and all had a KIT mutation in exon 11. Survival of patients with PMD was lower than with SMD or PMR. CONCLUSIONS: Metabolic response by 18F-FDG-PET/CT is associated with mutational status in metastatic melanoma patients treated with imatinib. 18F-FDG-PET/CT may be a predictor of outcome, although a larger study is needed to verify this.
    Cancer Imaging 11/2014; 14(1):30. · 1.29 Impact Factor
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    ABSTRACT: Ionizing radiation-mediated tumor regression depends on type I interferon (IFN) and the adaptive immune response, but several pathways control I IFN induction. Here, we demonstrate that adaptor protein STING, but not MyD88, is required for type I IFN-dependent antitumor effects of radiation. In dendritic cells (DCs), STING was required for IFN-? induction in response to irradiated-tumor cells. The cytosolic DNA sensor cyclic GMP-AMP (cGAMP) synthase (cGAS) mediated sensing of irradiated-tumor cells in DCs. Moreover, STING was essential for radiation-induced adaptive immune responses, which relied on type I IFN signaling on DCs. Exogenous IFN-? treatment rescued the cross-priming by cGAS or STING-deficient DCs. Accordingly, activation of STING by a second messenger cGAMP administration enhanced antitumor immunity induced by radiation. Thus radiation-mediated antitumor immunity in immunogenic tumors requires a functional cytosolic DNA-sensing pathway and suggests that cGAMP treatment might provide a new strategy to improve radiotherapy. Copyright © 2014 Elsevier Inc. All rights reserved.
    Immunity 11/2014; 41:843. · 19.75 Impact Factor
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    ABSTRACT: Spontaneous T cell responses against tumors occur frequently and have prognostic value in patients. The mechanism of innate immune sensing of immunogenic tumors leading to adaptive T cell responses remains undefined, although type I interferons (IFNs) are implicated in this process. We found that spontaneous CD8(+) T cell priming against tumors was defective in mice lacking stimulator of interferon genes complex (STING), but not other innate signaling pathways, suggesting involvement of a cytosolic DNA sensing pathway. In vitro, IFN-? production and dendritic cell activation were triggered by tumor-cell-derived DNA, via cyclic-GMP-AMP synthase (cGAS), STING, and interferon regulatory factor 3 (IRF3). In the tumor microenvironment in vivo, tumor cell DNA was detected within host antigen-presenting cells, which correlated with STING pathway activation and IFN-? production. Our results demonstrate that a major mechanism for innate immune sensing of cancer occurs via the host STING pathway, with major implications for cancer immunotherapy. Copyright © 2014 Elsevier Inc. All rights reserved.
    Immunity 11/2014; 41(5):830-842. · 19.75 Impact Factor
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    Sujit V Janardhan, Reinhard Marks, Thomas F Gajewski
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    ABSTRACT: Constitutive Ras signaling has been shown to augment IL-2 production, reverse anergy, and functionally replace many aspects of CD28 co-stimulation in CD4+ T cells. These data raise the possibility that introduction of active Ras into primary T cells might result in improved functionality in pathologic situations of T cell dysfunction, such as cancer or chronic viral infection. To test the biologic effects of active Ras in primary T cells, CD4+ T cells from Coxsackie-Adenovirus Receptor Transgenic mice were transduced with an adenovirus encoding active Ras. As expected, active Ras augmented IL-2 production in naive CD4+ T cells. However, when cells were cultured for 4 days under conditions to promote effector cell differentiation, active Ras inhibited the ability of CD4+ T cells to acquire a Th1 or Th2 effector cytokine profile. This differentiation defect was not due to deficient STAT4 or STAT6 activation by IL-12 or IL-4, respectively, nor was it associated with deficient induction of T-bet and GATA-3 expression. Impaired effector cytokine production in active Ras-transduced cells was associated with deficient demethylation of the IL-4 gene locus. Our results indicate that, despite augmenting acute activation of naïve T cells, constitutive Ras signaling inhibits the ability of CD4+ T cells to properly differentiate into Th1/Th2 effector cytokine-producing cells, in part by interfering with epigenetic modification of effector gene loci. Alternative strategies to potentiate Ras pathway signaling in T cells in a more regulated fashion should be considered as a therapeutic approach to improve immune responses in vivo.
    PLoS ONE 11/2014; 9(11):e112831. · 3.53 Impact Factor
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    ABSTRACT: The fourth ¿Melanoma Bridge Meeting¿ took place in Naples, December 5 to 8th, 2013. The four topics discussed at this meeting were: Diagnosis and New Procedures, Molecular Advances and Combination Therapies, News in Immunotherapy, and Tumor Microenvironment and Biomarkers.Until recently systemic therapy for metastatic melanoma patients was ineffective, but recent research in tumor biology and immunology has led to the development of new targeted and immunotherapeutic agents that prolong progression-free survival (PFS) and overall survival (OS). New therapies, such as mitogen-activated protein kinase (MAPK) pathway inhibitors, like BRAF and MEK inhibitors, as well as other signaling pathways inhibitors, are being tested in metastatic melanoma either as monotherapy or in combination, and have yielded promising results.Improved survival rates have also been observed with immune therapy for patients with metastatic melanoma. Immune-modulating antibodies came to the forefront with anti-CTLA-4, programmed cell death-1 (PD-1) and PD-1 ligand 1 (PD-L1) pathway blocking antibodies that result in durable responses in a subset of melanoma patients. Agents targeting other immune inhibitory (e.g., Tim-3) or immune stimulating (e.g., CD137) receptors and other approaches such as adoptive cell transfer demonstrate clinical benefit in melanoma as well.This meeting¿s specific focus was on advances in targeted therapy and immunotherapy. Both combination targeted therapy approaches and different immunotherapies were discussed. Similarly to the previous meetings, the importance of biomarkers for clinical application as markers for diagnosis, prognosis and prediction of treatment response was an integral part of the meeting. Significant consideration was given to issues surrounding the development of novel therapeutic targets as further study of patterns of resistance to both immunologic and targeted drugs are paramount to future drug development to guide existing and future therapies. The overall emphasis on biomarkers supports novel concepts toward integrating biomarkers into contemporary clinical management of patients with melanoma across the entire spectrum of disease stage. Translation of the knowledge gained from the biology of tumor microenvironment across different tumors represents a bridge to impact on prognosis and response to therapy in melanoma.
    Journal of Translational Medicine 10/2014; 12(1):277. · 3.99 Impact Factor
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    ABSTRACT: Endogenous type I IFN production after innate immune recognition of tumor cells is critical for generating natural adaptive immune responses against tumors in vivo. We recently have reported that targeting low doses of IFN-β to the tumor microenvironment using tumor-specific mAbs can facilitate antitumor immunity, which could be augmented further with PD-L1/PD-1 blockade. However, sustained high doses of type I IFNs in the tumor microenvironment, which are potently therapeutic alone, may function through distinct mechanisms. In the current report, we demonstrate that high-dose intratumoral type I IFNs indeed exerted a profound therapeutic effect in the murine B16 model, which unexpectedly did not increase T cell responses. Moreover, bone marrow chimeras revealed a role for type I IFN signaling on nonhematopoietic cells, and most of the therapeutic effect was retained in mice deficient in T, B, and NK cells. Rather, the tumor vasculature was ablated with high-dose intratumoral IFN-β, and conditional deletion of IFN-α/βR in Tie2-positive vascular endothelial cells eliminated most of the antitumor activity. Therefore, the major component of the antitumor activity of sustained high doses of type I IFNs occurs through a direct antiangiogenic effect. Our data help resolve conditions under which distinct antitumor mechanisms of type I IFNs are operational in vivo.
    Journal of immunology (Baltimore, Md. : 1950). 09/2014;
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    ABSTRACT: BACKGROUND Aberrant Notch activation confers a proliferative advantage to many human tumors, including melanoma. This phase 2 trial assessed the antitumor activity of RO4929097, a gamma-secretase inhibitor of Notch signaling, with respect to the progression-free and overall survival of patients with advanced melanoma.METHODS Chemotherapy-naive patients with metastatic melanoma of cutaneous or unknown origin were treated orally with RO4929097 at a dose of 20 mg daily 3 consecutive days per week. A 2-step accrual design was used with an interim analysis of the first 32 patients and with continuation of enrollment if 4 or more of the 32 patients responded.RESULTSThirty-six patients from 23 institutions were enrolled; 32 patients were evaluable. RO4929097 was well tolerated, and most toxicities were grade 1 or 2. The most common toxicities were nausea (53%), fatigue (41%), and anemia (22%). There was 1 confirmed partial response lasting 7 months, and there were 8 patients with stable disease lasting at least through week 12, with 1 of these continuing for 31 months. The 6-month progression-free survival rate was 9% (95% confidence interval [CI], 2%-22%), and the 1-year overall survival rate was 50% (95% CI, 32%-66%). Peripheral blood T-cell assays showed no significant inhibition of the production of interleukin-2, a surrogate pharmacodynamic marker of Notch inhibition, and this suggested that the drug levels were insufficient to achieve Notch target inhibition.CONCLUSIONSRO4929097 showed minimal clinical activity against metastatic melanoma in this phase 2 trial, possibly because of inadequate exposure to therapeutic drug levels. Although Notch inhibition remains a compelling target in melanoma, the results do not support further investigation of RO4929097 with this dose and schedule. Cancer 2014. © 2014 American Cancer Society.
    Cancer 09/2014; · 5.20 Impact Factor
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    ABSTRACT: Background Addition of a MEK inhibitor to a BRAF inhibitor enhances tumour growth inhibition, delays acquired resistance, and abrogates paradoxical activation of the MAPK pathway in preclinical models of BRAF-mutated melanoma. We assessed the safety and efficacy of combined BRAF inhibition with vemurafenib and MEK inhibition with cobimetinib in patients with advanced BRAF-mutated melanoma. Methods We undertook a phase 1b study in patients with advanced BRAFV600-mutated melanoma. We included individuals who had either recently progressed on vemurafenib or never received a BRAF inhibitor. In the dose-escalation phase of our study, patients received vemurafenib 720 mg or 960 mg twice a day continuously and cobimetinib 60 mg, 80 mg, or 100 mg once a day for either 14 days on and 14 days off (14/14), 21 days on and 7 days off (21/7), or continuously (28/0). The primary endpoint was safety of the drug combination and to identify dose-limiting toxic effects and the maximum tolerated dose. Efficacy was a key secondary endpoint. All patients treated with vemurafenib and cobimetinib were included in safety and efficacy analyses (intention-to-treat). The study completed accrual and all analyses are final. This study is registered with ClinicalTrials.gov, number NCT01271803. Findings 129 patients were treated at ten dosing regimens combining vemurafenib and cobimetinib: 66 had recently progressed on vemurafenib and 63 had never received a BRAF inhibitor. Dose-limiting toxic effects arose in four patients. One patient on a schedule of vemurafenib 960 mg twice a day and cobimetinib 80 mg once a day 14/14 had grade 3 fatigue for more than 7 days; one patient on a schedule of vemurafenib 960 mg twice a day and cobimetinib 60 mg once a day 21/7 had a grade 3 prolongation of QTc; and two patients on a schedule of vemurafenib 960 mg twice a day and cobimetinib 60 mg 28/0 had dose-limiting toxic effects—one developed grade 3 stomatitis and fatigue and one developed arthralgia and myalgia. The maximum tolerated dose was established as vemurafenib 960 mg twice a day in combination with cobimetinib 60 mg 21/7. Across all dosing regimens, the most common adverse events were diarrhoea (83 patients, 64%), non-acneiform rash (77 patients, 60%), liver enzyme abnormalities (64 patients, 50%), fatigue (62 patients, 48%), nausea (58 patients, 45%), and photosensitivity (52 patients, 40%). Most adverse events were mild-to-moderate in severity. The most common grade 3 or 4 adverse events were cutaneous squamous-cell carcinoma (12 patients, 9%; all grade 3), raised amounts of alkaline phosphatase (11 patients, 9%]), and anaemia (nine patients, 7%). Confirmed objective responses were recorded in ten (15%) of 66 patients who had recently progressed on vemurafenib, with a median progression-free survival of 2·8 months (95% CI 2·6–3·4). Confirmed objective responses were noted in 55 (87%) of 63 patients who had never received a BRAF inhibitor, including six (10%) who had a complete response; median progression-free survival was 13·7 months (95% CI 10·1–17·5). Interpretation The combination of vemurafenib and cobimetinib was safe and tolerable when administered at the respective maximum tolerated doses. The combination has promising antitumour activity and further clinical development is warranted in patients with advanced BRAFV600-mutated melanoma, particularly in those who have never received a BRAF inhibitor; confirmatory clinical testing is ongoing. Funding F Hoffmann-La Roche/Genentech.
    The Lancet Oncology 08/2014; · 24.73 Impact Factor
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    ABSTRACT: Uveal melanoma is characterized by mutations in GNAQ and GNA11, resulting in mitogen-activated protein kinase pathway activation.
    JAMA The Journal of the American Medical Association 06/2014; 311(23):2397-405. · 30.39 Impact Factor
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    ABSTRACT: Antibodies (Abs) that preferentially target oncogenic receptors have been increasingly used for cancer therapy, but tumors often acquire intrinsic Ab resistance after prolonged and costly treatment. Herein we armed the Ab with IFNβ and observed that it is more potent than the first generation of Ab for controlling Ab-resistant tumors. This strategy controls Ab resistance by rebridging suppressed innate and adaptive immunity in the tumor microenvironment. Mechanistically, Ab-IFNβ therapy primarily and directly targets intratumoral dendritic cells, which reactivate CTL by increasing antigen cross-presentation within the tumor microenvironment. Additionally, blocking PD-L1, which is induced by Ab-IFNβ treatment, overcomes treatment-acquired resistance and completely eradicates established tumors. This study establishes a next-generation Ab-based immunotherapy that targets and eradicates established Ab-resistant tumors.
    Cancer cell 01/2014; 25(1):37-48. · 25.29 Impact Factor
  • Journal of Translational Medicine 01/2014; 12(Suppl 1):O7. · 3.99 Impact Factor
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    ABSTRACT: Blockade of immune inhibitory pathways is emerging as an important therapeutic modality for the treatment of cancer. Single agent treatments have partial anti-tumor activity in preclinical models and in human cancer patients. Inasmuch as the tumor microenvironment shows evidence of multiple immune inhibitory mechanisms present concurrently, it has been reasoned that combination therapies may be required for optimal therapeutic effect. To test this notion, we utilized permutations of anti-CTLA-4 mAb, anti-PD-L1 mAb, and/or the IDO inhibitor INCB23843 in the murine B16.SIY melanoma model. All three combinations showed markedly improved tumor control over single treatments, with many mice achieving complete tumor rejection. This effect was seen in the absence of vaccination or adoptive T cell therapy. The mechanism of synergy was investigated to examine the priming versus effector phase of the anti-tumor immune response. Only a minimal increase in priming of anti-tumor T cells was observed at early time points in the tumor-draining lymph nodes (TdLN). In contrast, as early as three days after therapy initiation, a marked increase in the capacity of tumor-infiltrating CD8(+) T cells to produce IL-2 and to proliferate was found in all groups treated with the effective combinations. Treatment of mice with FTY720 to block new T cell trafficking from secondary lymphoid structures still enabled restoration of IL-2 production and proliferation by intratumoral T cells, and also retained most of the tumor growth control. Our data suggest that the therapeutic effect of these immunotherapies was mainly mediated through direct reactivation of T cells in situ. These three combinations are attractive to pursue clinically, and the ability of intratumoral CD8(+) T cells to produce IL-2 and to proliferate could be an important biomarker to integrate into clinical studies.
    Journal for immunotherapy of cancer. 01/2014; 2:3.
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    Thomas F Gajewski, Hans Schreiber, Yang-Xin Fu
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    ABSTRACT: Most tumor cells express antigens that can mediate recognition by host CD8(+) T cells. Cancers that are detected clinically must have evaded antitumor immune responses to grow progressively. Recent work has suggested two broad categories of tumor escape based on cellular and molecular characteristics of the tumor microenvironment. One major subset shows a T cell-inflamed phenotype consisting of infiltrating T cells, a broad chemokine profile and a type I interferon signature indicative of innate immune activation. These tumors appear to resist immune attack through the dominant inhibitory effects of immune system-suppressive pathways. The other major phenotype lacks this T cell-inflamed phenotype and appears to resist immune attack through immune system exclusion or ignorance. These two major phenotypes of tumor microenvironment may require distinct immunotherapeutic interventions for maximal therapeutic effect.
    Nature Immunology 10/2013; 14(10):1014-22. · 24.97 Impact Factor
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    ABSTRACT: Tumor escape from immune-mediated destruction has been associated with immunosuppressive mechanisms that inhibit T cell activation. Although evidence for an active immune response, including infiltration with CD8(+) T cells, can be found in a subset of patients, those tumors are nonetheless not immunologically rejected. In the current report, we show that it is the subset of T cell-inflamed tumors that showed high expression of three defined immunosuppressive mechanisms: indoleamine-2,3-dioxygenase (IDO), PD-L1/B7-H1, and FoxP3(+) regulatory T cells (Tregs), suggesting that these inhibitory pathways might serve as negative feedback mechanisms that followed, rather than preceded, CD8(+) T cell infiltration. Mechanistic studies in mice revealed that up-regulated expression of IDO and PD-L1, as well as recruitment of Tregs, in the tumor microenvironment depended on the presence of CD8(+) T cells. The former was driven by interferon-γ and the latter by a production of CCR4-binding chemokines along with a component of induced proliferation. Our results argue that these major immunosuppressive pathways are intrinsically driven by the immune system rather than being orchestrated by cancer cells, and imply that cancer immunotherapy approaches targeting negative regulatory immune checkpoints might be preferentially beneficial for patients with a preexisting T cell-inflamed tumor microenvironment.
    Science translational medicine 08/2013; 5(200):200ra116. · 14.41 Impact Factor
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    ABSTRACT: Immunotherapy is associated with durable clinical benefit in patients with melanoma. The goal of this article is to provide evidence-based consensus recommendations for the use of immunotherapy in the clinical management of patients with high-risk and advanced-stage melanoma in the USA. To achieve this goal, the Society for Immunotherapy of Cancer sponsored a panel of melanoma experts-including physicians, nurses, and patient advocates-to develop a consensus for the clinical application of tumour immunotherapy for patients with melanoma. The Institute of Medicine clinical practice guidelines were used as a basis for this consensus development. A systematic literature search was performed for high-impact studies in English between 1992 and 2012 and was supplemented as appropriate by the panel. This consensus report focuses on issues related to patient selection, toxicity management, clinical end points and sequencing or combination of therapy. The literature review and consensus panel voting and discussion were used to generate recommendations for the use of immunotherapy in patients with melanoma, and to assess and rate the strength of the supporting evidence. From the peer-reviewed literature the consensus panel identified a role for interferon-α2b, pegylated-interferon-α2b, interleukin-2 (IL-2) and ipilimumab in the clinical management of melanoma. Expert recommendations for how to incorporate these agents into the therapeutic approach to melanoma are provided in this consensus statement. Tumour immunotherapy is a useful therapeutic strategy in the management of patients with melanoma and evidence-based consensus recommendations for clinical integration are provided and will be updated as warranted.
    Nature Reviews Clinical Oncology 08/2013; · 15.03 Impact Factor
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    ABSTRACT: PTEN is thought to play a critical role in T cell activation by negatively regulating the PI3K signaling pathway important for cellular activation, growth, and proliferation. To directly eliminate PTEN in postthymic T cells for studies of functional effects, we used CAR transgenic × PTEN(flox/flox) mice, which enabled gene deletion using a Cre adenovirus in vitro. These mice were also immunized to generate stable Th1 clones that could have PTEN deleted when desired. PTEN-deleted T cells exhibited enhanced IL-2 production, proliferation, and Akt phosphorylation upon TCR/CD28 engagement, whereas T cell survival was not potentiated. Gene expression profiling revealed a small subset of induced genes that were augmented upon PTEN deletion. However, PTEN-deficient T cells still required CD28 costimulation for IL-2 production and remained susceptible to anti-CD3-induced anergy. The absence of PTEN within the CD8 T cell compartment led to markedly increased cytolytic activity following an allogeneic MLR in vitro, without increasing autologous MLR activity. Our results indicate that deletion of PTEN can augment the activation of postthymic T cells but does not mediate CD28 independence or anergy resistance. Nonetheless, PTEN inhibition may be a viable target for immune potentiation owing to increased cytokine production by activated CD4(+) cells and increased cytotoxicity by CD8(+) T cells.
    The Journal of Immunology 07/2013; 191(4). · 5.36 Impact Factor
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    ABSTRACT: PURPOSEAmplifications and mutations in the KIT proto-oncogene in subsets of melanomas provide therapeutic opportunities. PATIENTS AND METHODS We conducted a multicenter phase II trial of imatinib in metastatic mucosal, acral, or chronically sun-damaged (CSD) melanoma with KIT amplifications and/or mutations. Patients received imatinib 400 mg once per day or 400 mg twice per day if there was no initial response. Dose reductions were permitted for treatment-related toxicities. Additional oncogene mutation screening was performed by mass spectroscopy.ResultsTwenty-five patients were enrolled (24 evaluable). Eight patients (33%) had tumors with KIT mutations, 11 (46%) with KIT amplifications, and five (21%) with both. Median follow-up was 10.6 months (range, 3.7 to 27.1 months). Best overall response rate (BORR) was 29% (21% excluding nonconfirmed responses) with a two-stage 95% CI of 13% to 51%. BORR was significantly greater than the hypothesized null of 5% and statistically significantly different by mutation status (7 of 13 or 54% KIT mutated v 0% KIT amplified only). There were no statistical differences in rates of progression or survival by mutation status or by melanoma site. The overall disease control rate was 50% but varied significantly by KIT mutation status (77% mutated v 18% amplified). Four patients harbored pretreatment NRAS mutations, and one patient acquired increased KIT amplification after treatment. CONCLUSION Melanomas that arise on mucosal, acral, or CSD skin should be assessed for KIT mutations. Imatinib can be effective when tumors harbor KIT mutations, but not if KIT is amplified only. NRAS mutations and KIT copy number gain may be mechanisms of therapeutic resistance to imatinib.
    Journal of Clinical Oncology 06/2013; · 17.88 Impact Factor
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    ABSTRACT: Recent insights into the genetic and somatic aberrations have initiated a new era of rapidly evolving targeted and immune-based treatments for melanoma. After decades of unsuccessful attempts to finding a more effective cure in the treatment of melanoma now we have several drugs active in melanoma. The possibility to use these drugs in combination to improve responses to overcome the resistance, to potentiate the action of immune system with the new immunomodulating antibodies, and identification of biomarkers that can predict the response to a particular therapy represent new concepts and approaches in the clinical management of melanoma. The third "Melanoma Research: "A bridge from Naples to the World" meeting, shortened as "Bridge Melanoma Meeting" took place in Naples, December 2 to 4th, 2012. The four topics of discussion at this meeting were: advances in molecular profiling and novel biomarkers, combination therapies, novel concepts toward integrating biomarkers and therapies into contemporary clinical management of patients with melanoma across the entire spectrum of disease stage, and the knowledge gained from the biology of tumor microenvironment across different tumors as a bridge to impact on prognosis and response to therapy in melanoma. This international congress gathered more than 30 international faculty members who in an interactive atmosphere which stimulated discussion and exchange of their experience regarding the most recent advances in research and clinical management of melanoma patients.
    Journal of Translational Medicine 06/2013; 11(1):137. · 3.99 Impact Factor
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    ABSTRACT: Spontaneous antigen-specific T cell responses can be generated in hosts harboring a variety of solid malignancies, but are subverted by immune evasion mechanisms active within the tumor microenvironment. In contrast to solid tumors, the mechanisms that regulate T cell activation versus tolerance to hematological malignancies have been underexplored. A murine acute myeloid leukemia (AML) model was used to investigate antigen-specific T cell responses against AML cells inoculated i.v. versus s.c. Robust antigen-specific T cell responses were generated against AML cells after s.c., but not i.v., inoculation. In fact, i.v. AML cell inoculation prevented functional T cell activation in response to subsequent s.c. AML cell challenge. T cell dysfunction was antigen specific and did not depend on Tregs or myeloid-derived suppressor cells (MDSCs). Antigen-specific TCR-Tg CD8+ T cells proliferated, but failed to accumulate, and expressed low levels of effector cytokines in hosts after i.v. AML induction, consistent with abortive T cell activation and peripheral tolerance. Administration of agonistic anti-CD40 Ab to activate host APCs enhanced accumulation of functional T cells and prolonged survival. Our results suggest that antigen-specific T cell tolerance is a potent immune evasion mechanism in hosts with AML that can be reversed in vivo after CD40 engagement.
    The Journal of clinical investigation 04/2013; · 15.39 Impact Factor

Publication Stats

9k Citations
1,370.20 Total Impact Points

Institutions

  • 1988–2014
    • University of Illinois at Chicago
      • • Department of Medicine (Chicago)
      • • Section of Hematology and Oncology
      • • Department of Pathology (Chicago)
      Chicago, Illinois, United States
    • University of Chicago
      • • Committee on Immunology
      • • Department of Pathology
      • • Section of Hematology/Oncology
      • • Department of Medicine
      Chicago, Illinois, United States
  • 2013
    • Sidra Medical and Research Cente
      Ad Dawḩah, Ad Dawḩah, Qatar
    • Institut de Cancérologie Gustave Roussy
      Île-de-France, France
  • 1995–2012
    • The University of Chicago Medical Center
      • • Department of Medicine
      • • Section of Hematology/Oncology
      • • Department of Pathology
      Chicago, IL, United States
    • Ludwig Institute for Cancer Research
      La Jolla, California, United States
  • 1998
    • Howard Hughes Medical Institute
      Ashburn, Virginia, United States
  • 1997
    • University of Illinois, Urbana-Champaign
      • Department of Biochemistry
      Urbana, IL, United States
  • 1996
    • Ludwig Institute for Cancer Research Ltd Belgium
      Bruxelles, Brussels Capital Region, Belgium
  • 1995–1996
    • Catholic University of Louvain
      • Duve Institute
      Walloon Region, Belgium
  • 1993
    • University of Iowa
      Iowa City, Iowa, United States